Question

A golf ball with a mass of 45 g is rolling down a hill. At the bottom of the hill, its speed is 6 m/s. What is its GPE?

Answer 1

GPE = 0 (when the golf is downhill)

GPE = 0.81 [J](when the golf is at the highest point of the hill)

Step-by-step explanation:

In order to solve this problem, we must use the principle of energy conservation, which tells us that energy is transformed from kinetic energy to potential energy or vice versa.

We must define a reference energy point, where at this point the potential energy is zero. Let's take this point at the bottom of the hill.

At this point where the potential energy is zero, all the potential energy will have been transformed into kinetic energy, at this point the velocity will be maximum.

`E_k=E_p\\where:\\E_(p)=m*g*h\\E_(k)=(1)/(2) *m*v^(2)`

where:

m = mass = 45 [g] = 0.045 [kg]

g = gravity acceleration = 9.81 {m/s²]

h = elevation [m]

v = velocity = 6 [m/s]

`E_(k)=(1)/(2)*0.045*(6)^(2) \\E_(k)=E_(p)=0.81 [J]`

GPE = 0 (when the golf is downhill)

GPE = 0.81 [J](when the golf is at the highest point of the hill)